Tsunade needs Kakashi to provide the Village with a new Hatake before his self-destructive tendencies kill him. Naruto needs an Uzumaki heir to pass Kyuubi to. Unwilling to see his sensei forced into something that would hurt him, Naruto proposes a solution that kills two birds with a stone. It's a ninja's duty to help his Village and his friends. Unless he's the one to get hurt.